This manuscript reviews recent results of large scale shell model calculations for N = Z nuclei. The topics discussed include the role of the proton-neutron pairing in determining the binding energies of pf shell nuclei and properties of backbending rotors, as well as the Coulomb energy differences and their relationship with alignment. Proton-neutron correlations are found responsible for the characteristic features of the isotopic shifts in calcium, i.e., for the parabolic dependence on A and prominent odd-even staggering.